DALLAS (CBSFDW.COM) – An off-site power surge is believed to be the reason the Dallas Zoo’s Monorail Safari electric train stopped Wednesday with 48 guests and one driver on board.

The monorail will remain closed until at least Friday while engineering crews inspect three trains and the track for any electrical damage.

It came to a halt around 11:30 a.m. in an area covered with trees, which provided much-needed shade.

Dallas Zoo crews realized their own ladders were about a foot too short to reach the passengers so they called Dallas Fire Rescue.

The passengers were given water, ice and snacks as they waited for fire crews to help them down.

Fire crews brought passengers down several ladders, one-by-one.

The Minter family, from Midlothian, went to the zoo with their 2-year-old.

“It was a little scary when they told me the fire department was coming and they were going to have to carry my baby down,” Christina Minter said. “But it was okay. They scaled that fence like nobody I’ve ever seen. They got us down so everything was great.”

The families were given free tickets to the Dallas Zoo for a return visit. Many of them planned to return.

The popular Monorail Safari is 24 years old. Long-term, the zoo is looking at options for the Wilds of Africa habitat which the Monorail overlooks, which would include replacing the monorail. As a non-profit zoological park, private funding would be required for such a project.